Green Day frontman Billie Joe Armstrong could be in rehab until next year

The Green
Day frontman went into treatment for substance abuse problems in September after he smashed a guitar and swore multiple times on stage in Las Vegas.

Now his
record label boss Rob Cavallo has confirmed he may need to be in for some time.

In rehab: Green Day's Billie Joe Armstrong could remain in treatment until next year, according to reports

He told Rolling
Stonemagazine: 'He's under medical supervision for a while to get him
clean. His doctors are still evaluating'

'All I
can say is I don't know if we'll see him before or after Christmas. It's
basically undetermined when he will be back'

Billie Joe
was said to be considered a loose cannon for some time prior to his rehab
entry, with friends saying it was about time he got serious help
for his problems.

A source
said: 'Billie Joe has been a loose cannon for a long time. It's gone long
past time when he should be getting some serious help.'

The
outburst prior to his checking in at rehab began when a teleprompter at the
iHeartRadio festival in Las Vegas urged him to finish performing in one minute.

He said: 'You're going to give me one minute? One f**king minute? I've been
around since f**king 19 f**king 80 f**king eight, and you're going to give me
one f**king minute? I'm not f**king Justin Bieber, you motherf**kers.'

He then
destroyed his guitar and left the stage.

Last week, Green Day bassist Mike Dirnt told BBC Radio 1 host Zane Lowe that the pressure to promote their three new albums ¡Uno!, ¡Dos! and ¡Tre! had put a heavy burden on the band.

'With hindsight 20/20, it was a tremendous undertaking,' Dirnt said. 'Although we were having fun, we didn't take our nose out of the book for a long time.'

'I think it catches up with you a little bit. We definitely just jumped off a moving train.'

The bassist also said that Armstrong's Vegas incident had not come as a complete surprise after he band were also forced to cancel a show in Bologna in September after Armstrong was hospitalized hours before they were due to take the stage.

'There were signs of things hitting the fan,' he admitted. 'We hadn't slept in forever and Billie had definitely had the worst of it.'

'He'd been going through his own struggles . . . We were there with him, but you can only handle things on your own . . . At the end of the day, when we got off the road, the most important thing was my friend's life.'